Funny AC noise - Toyota Nation Forum : Toyota Car and Truck Forums

noname87 · 03-23-2011, 08:18 PM

I tried posting this before but it didn't appear.

I have a 95 wagon with the 4 cyc engine. I had my AC (compressor, clutch. dryer) replaced in August. Since that time, whenever the compressor kicks on, I get this wierd sound. It is hard to described. It is loke a short whooping sound or a sound a stuck door might make when pulled open. The mechanic says it could be a damper in the dash. I find it odd this started immediately after replacing the AC. Last week, the compressor stared to fail and was replaced under warranty. Since then, it still makes the sound but less frequaently. With the hood open, it doesn't seem to be coming from the compresor. What could be causing this?

1steve · 03-23-2011, 09:04 PM

Hello, was there any work done to the evaporator core or expansion valve?

noname87 · 03-24-2011, 01:14 AM

According to the reciept, the A/C compressor kit inclued the drier, flush, oil, expansion valve. The clutch was also replace.

Stillrunning · 03-24-2011, 06:50 AM

The expansion valve is located under the dash. Is it possible this sound is coming from under the dash about mid point?

noname87 · 03-24-2011, 10:26 AM

I will check it out. If this is the issue, what can I do about it?

Stillrunning · 03-24-2011, 10:39 AM

Quote:

Originally Posted by noname87

If this is the issue, what can I do about it?

Good question, I don't have a good answer. First are you getting adequate cooling? If the expansion valve is the culprit then it may be setting up a resonance as it opens and closes and refrigerant passes through the orifice. The expansion valve may be a cheap aftermarket and/or may be defective. First you need to make sure there is the proper amount of refrigerant in the system and pressures are correct.

noname87 · 03-24-2011, 11:08 AM

Plenty of cold air. For waht I paid, I should see snow.

If I can isolate the sound, I can take it back to the mechanic. Last time, he claimed it was coming from the dash. He said ther is a flapper of some sort that controls the air flow that could be causing it. Since it never made the sound before the new system, I have my doubts.

Stillrunning · 03-24-2011, 01:24 PM

Quote:

Originally Posted by noname87

He said ther is a flapper of some sort that controls the air flow that could be causing it. I have my doubts.

Some air vent flow controls use vacuum so when there is a leak they can whistle. I can't remember if the 95 uses vacuum or electrics to open/close the air vents, maybe someone else here can answer that. It may be coincidence that this happened just as you had your A/C worked on, but I seldom believe in coincidence. Since the mechanic would have been under the dash to replace the expansion valve he may have broken a connection or loosened one. Make sure all your vents are working as you run through the selector switch.